Recent trends indicated that the existing process/thread support provided by systems in unsuitable for a range of application programs. A new processing paradigm is now evolving to fill this gap and to provide more flexibility to distribute tasks across processes/threads. This emerging paradigm allows multiple program threads to work on the task, each thread to work on a different task, or a thread to work on multiple task for greater design flexibility or due to system constraints such as real-time demands and a high load on tasking. We use the definition of context to capture the notion of logical locus of control. The context of the work being currently executed must be identifiable uniquely by the application, the Resource Managers and the Transaction Manager because each context represents different work. In this work we have identified this emerging paradigm, defined context, the Context manager and its user interface, and show how context is used for local and distributed transaction processing. We high-light the role of context in a multithreaded, real-time, high tasking operating environment, provide different practical styles of transaction management using context, and show how to use context management to solve deadlocks, protocol violations and loopbacks. The result of this work has been published in "Context Management and its Applications to Distributed Transactions". The VM operating Shared File System has been enhanced to provide a version of the context management support presented in this work. An expanded version of the prementioned paper has been submitted for further publication. This work also clarifies XOPEN's/XA++ recently identified problems regarding the vagueness surrounding the notion of "thread of control".

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